Over 50 per cent of the county area is judged of national interest to nature conservation or for outdoor life, but only 4 per cent of the county area is protected countryside.
As technology has developed, mankind has begun to influence the environment in such a way that the natural ecocycles have been disturbed. Acidification is primarily accelerated by fallout of sulphurous compounds. Carbon dioxide increases the greenhouse effect. Together with water vapour and certain other gases, carbon dioxide absorbs heat radiation. This does not prevent the heat from sunlight from reaching the earth's surface, but it does effectively prevent heat radiation from the earth from dispersing into space.